Re: [Help-glpk] WG: Information about unbound systems?

[Brady Hunsaker]

Stefan Herbergs wrote:
> Hi everybody,
> 
> I need to find out wheter a MIP is solveable, unsolveable or unbound. Is
> there a way to do that? The lpx_mip_status function doesn`t return UNBND in
> any way. Or did I get something wrong here? I'm using GLPK 4.8 with VC.NET.
> 
> Thank you very much
> 
> Stefan
> 

I can't remember whether GLPK checks for unboundedness.  Except in some
pathological instances, a MIP is unbounded if and only if the LP
relaxation is unbounded.  First solve the relaxation--if it's unbounded
then your MIP is almost certainly unbounded.

Brady


Brady Hunsaker
Assistant Professor
Industrial Engineering
University of Pittsburgh
http://www.engr.pitt.edu/hunsaker/